Film case for x-ray camera

ABSTRACT

The present invention relates to a film casing for an X-ray camera, the casing being of the type generally constituting a cylindric tube into which a film carrier of an X-ray picture is to be introduced for exposure in close contact with the internal surface of the tube. On both sides of the space for a film introduced into the tube for exposure, as seen in the axial direction of the tube, the casing comprises an annular clamping means to hold edges of the film in position inside the tube, said clamping means comprising a flange protruding axially into the tube from the end thereof and being provided with slots allowing for radial widening and compressing of the clamping means for fastening and loosening, respectively, a film introduced between the flange and the internal surface of the tube. The annular clamping means further comprise an abutment surface arranged to cooperate with an abutment surface of the tube to restrict the movement of the annular clamping means in the axial direction of the tube, the clamping means further being cooperative with an axially adjustable member by abutment means, of which at least one constitutes an acute angle with the axis of the tube as seen in a radial plane through said axis in the longitudinal direction thereof.

United States Patent Morichetto (54] FlLM CASE FOR X-RAY CAMERA [72] Inventor:

[73] Assignee:

Michele Morichetto, Spanga, Sweden Incentive Research & Development AB, Bromma, Sweden [22] Filed: Aug.il, 1970 [21] Appl.No.: 62,941

[30] Foreign Application Priority Data Aug. 12, 1969 Sweden ..ll222/69 [52] US. Cl ..250/68, 95/31 CA, 206/52 F, 250/5 1.5

[51] Int. Cl. ..G0ln 23/20 [58] Field of Search 206/62 R; 250/65, 68, 51.5; 95/31 R, 31 CA 3,341,001 9/1967 Barclay et a1 4206/52 F Primary Examiner-Anthony L. Birch Attorney-Waters, Roditi, Schwartz & Nissen Feb. 1, 1972 [5 7] ABSTRACT The present invention relates to a film casing for an X-ray camera, the casing being of the type generally constituting a cylindric tube into which a film carrier of an X-ray picture is to be introduced for exposure in close contact with the internal surface of the tube. On both sides of the space for a film introduced into the tube for exposure, as seen in the axial direction of the tube, the casing comprises an annular clamping means to hold edges of the film in position inside the tube, said clamping means comprising a flange protruding axially into the tube from the end thereof and being provided with slots allowing for radial widening and compressing of the clamping means for fastening and loosening, respectively, a film introduced between the flange and the internal surface of the tube. The annular clamping means further comprise an abutment surface arranged to cooperate with an abutment surface of the tube to restrict the movement of the annular clamping means in the axial direction of the tube, the clamping means further being cooperative with an axially adjustable member by abutment means, of which at least one constitutes an acute angle with the axis of the tube as seen in a radial plane through said axis in the longitudinal direction thereof.

6 Claims, 3 Drawing Figures PATEIIEBFII 1972 3639361 sum 1 or 2 F/gl FILM CASE FOR X-RAY CAMERA BACKGROUND OF THE INVENTION This invention relates to a film casing for an X-ray camera and in particular a casing of the kind generally constituting a cylindric tube, within which a film is to be inserted in contact with the internal surface of the tube, said contact to be as close as possible.

OBJECT AND SUMMARY OF THE INVENTION A major object of the invention is to provide a casing of the kind which is easy to load and in which the film can be brought into an extremely accurate contact with the internal mantle surface of the case tube.

For this purpose a film case for an X-ray camera of the kind comprising a cylindric. tube in which, when the case is used, an X-ray sensitive carrier in form of a film is to be introduced in tight contact to the internal surface of the tube, further comprises, according to the invention, at each end of the tube, an annularly extending clamping means to force edges of said carrier toward the internal surface of the tube, said means having a flange extending into the tube at the end thereof and being provided with at least one cut allowing for expansion and contraction of the clamping means for fastening and loosening, respectively, a film introduced between said flange and the internal surface of the tube, said clamping means further comprising an abutment surface to cooperate with an axially effective stationary abutment surface of the case to axially restrict movement of said clamping means, said annularly extending clamping means further comprising peripherically extending abutment surfaces to cooperate with peripherically extending abutment surfaces of an actuating member axially adjustable relative to the tube, at least one of said peripherically extending abutment surfaces of said clamping means and said adjustable member constituting an acute angle with the tube axis as seen in an axial plane.

In a preferred embodiment said annularly extending clamping means comprises a number of separate ring segments which together form an expandable and retractable clamping means held together by being located radially between the tube and the axially adjustable actuating member.

The axially adjustable actuating member axially cooperating with the clamping means consists, in a further preferred embodiment, of a threaded ring carried on the end of the tube on a corresponding thread and being adjustable to force a conical abutment surface toward one or more peripherical abutment surfaces of the clamping means to thusforce corresponding flange portions of the clamping means toward the internal surface of the tube.

Preferably, the annularly extending clamping means and the axially adjustable actuating member cooperative therewith have each mutually mating and substantially conical abutment surfaces to effect expansion of the clamping means by axially moving the actuating member.

In a preferred embodiment, in which the annularly extending clamping means comprises a number of individual segments, the clamping means further comprises a peripherically extending resilient means acting to move the segments of the clamping means toward the tube axis.

In a further preferred embodiment, the casing comprises means restricting the movement of the clamping means axially in a direction away from the stationary abutment surface of the tube, to hold the clamping means in position when loosened.

An embodiment according to the invention will now be further described with reference to the accompanying drawings, on which FIG. 1 shows a case according to the invention as viewed perpendicular to the axis thereof,

FIG. 2 is a section through the case along the line II-ll of FIG. 1, and

FIG. 3 is a section through the clamping means at one end of the case showing the adjustable member and conical annularly extending member cooperating therewith in'an embodiment in which the clamping means is subdivided into a number of segments.

The case comprises a cylindric tube 1, out of which is cut an aperture for introducing a photographic film. The aperture is closable by a lockable lid 2, in a part constituting an integrating portion of the mantle of the tube, so that, when the lid is in place, the tube has an even, in this case circularly cylindric surface constituting the intended abutment surface for a film introduced through the aperture of the tube 1.

To hold the film in position within the tube, the case comprises at each end thereof an annular clamping means 3, said clamping means having an abutment surface 11, cooperative with an abutment surface 10 of the tube, and a flange l2 protruding into the tube, the flange being so arranged that it is cooperative with the cylindric internal wall 13 of the tube when the clamping means 3 is expanded to hold an X-ray sensitive film at the edges thereof extending peripherically along the internal surface of the tubes and located between the flange l2 and the tube surface 13. The annular clamping means 3, which is thus expandable to hold a film tight between the flange l2 and thesurface 13, could, generally speaking, be made so that, as a limit, it comprises one single cut only, allowing for the necessary expansion of the clamping means. Preferably, however, the annular clamping means is subdivided in a number of ring segments, for instance, as illustrated in FIG. 3, each extending peripherically about a center angle of 45. By this measure, expansion of the annular clamping means into contact with a film to hold the film tight to the tube surface is provided for under a comparatively small displacement peripherically between cooperating surfaces, in that the mutual distance between the plurality of segments 14 increase during the expansion of the annular clamping means.

To attain expansion of the annular clamping means, that is, in the embodiment as illustrated, the separation of the segments 14, for fastening a film, a wedge action is provided between a sloping, generally conical abutment surface 15 of the annular clamping means 3, this abutment surface 15 cooperating with a corresponding sloping abutment surface 16 of a pressure ring 5 constituting part of or, as illustrated, arranged within an actuating end ring 8 which by means of threads 17 is screwed onto a corresponding thread 18 of the tube and serves as an ultimate actuating member for locking and loosening a film.

The segments 14 are held axially by a guide ring 4 engaging a radial and peripheral slot 19 of each segment. Further, the segments are jointly under the action of a radial spring force effected by a circular resilient ring -6-tending to move the segments inwardly when the corresponding actuating end ring is loosened by being unscrewed, thus leaving between the flanges 12 of the segments and the internal cylinder surface a space for introducing or removing a film through the aperture of the case after removing the lid.

On the drawing, only one end of the case is illustrated in detail, the construction of the another end being identical.

Lid 2 could be secured to the rest of the case by any convenient means, said means in the embodiment as illustrated comprising an extending portion at one longitudinal edge of the lid, mating with a corresponding groove in a longitudinal edge of the tube wall, the lid at the opposite longitudinal edge being held by a retractable pin entering a corresponding bore in the edge of the tube wall.

What is claimed is:

l. A film case for an X-ray camera of the kind comprising a cylindric tube in which, when the case is used, an X-ray sensitive carrier in the form of a film is to be introduced in tight contact to the internal surface of the tube, characterized by the fact that the film case comprises, at each end of the tube, an annularly extending clamping means to force edges of said film toward the internal surface of the tube, said means having a flange extending into the tube at the end thereof and being provided with at least one cut allowing for expansion and contraction of the clamping means for fastening and loosening,

respectively, a film introduced between said flange and the internal surface of the tube, said clamping means further comprising an abutment surface to cooperate with an axially effective stationary abutment surface of the tube case to axially restrict movement of said clamping means, said annularly extending clamping means further comprising peripherically extending abutment surfaces to cooperate with peripherically extending abutment surfaces of an actuating member axially adjustable relative to the tube, at least one of said peripherically extending abutment surfaces of said clamping means and said adjustable member constituting an acute angle with the tube axis as seen in an axial plane.

2. A film case according to claim 1, characterized by the fact that said annularly extending clamping means comprises asaid ring being adjustable to force a conical abutment surface toward one or more peripheries] abutment surfaces of the clamping means to thus force corresponding flange portions of the clamping means toward the internal surface of the tube.

4. A film case according to claim 1, characterized by the fact that the annularly extending clamping means and the axially adjustable actuating member cooperative therewith have each mutually mating and substantially conical abutment surfaces to efiect expansion of the clamping means by axially moving the actuating member.

5. A film case according to claim 2, characterized by the fact that said clamping means further comprise a peripherically extending resilient means acting to move the segments of the clamping means toward the tube axis.

6. A film case according to claim 1, characterized by the fact that it comprises means restricting the movement of the clamping means axially in a direction away from said stationary abutment surface.

*' =0 e a a 

1. A film case for an X-ray camera of the kind comprising a cylindric tube in which, when the case is used, an X-ray sensitive carrier in the form of a film is to be introduced in tight contact to the internal surface of the tube, characterized by the fact that the film case comprises, at each end of the tube, an annularly extending clamping means to force edges of said film toward the internal surface of the tube, said means having a flange extending into the tube at the end thereof and being provided with at least one cut allowing for expansion and contraction of the clamping means for fastening and loosening, respectively, a film introduced between said flange and the internal surface of the tube, said clamping means further comprising an abutment surface to cooperate with an axially effective stationary abutment surface of the tube case to axially restrict movement of said clamping means, said annularly extending clamping means further comprising peripherically extending abutment surfaces to cooperate with peripherically extending abutment surfaces of an actuating member axially adjustable relative to the tube, at least one of said peripherically extending abutment surfaces of said clamping means and said adjustable member constituting an acute angle with the tube axis as seen in an axial plane.
 2. A film case according to claim 1, characterized by the fact that said annularly extending clamping means comprises a number of separate ring segments.
 3. A film case according to claim 1, characterized by the fact that said axially adjustable actuating member axially cooperating with the clamping means consists of a threaded ring carried on the end of the tube on a corresponding thread, said ring being adjustable to force a conical abutment surface toward one or more peripherical abutment surfaces of the clamping means to thus force corresponding flange portions of the clamping means toward the internal surface of the tube.
 4. A film case according to claim 1, characterized by the fact that the annularly extending clamping means and the axially adjustable actuating member cooperative therewith have each mutually mating and substantially conical abutment surfaces to effect expansion of the clamping means by axially moving the actuating member.
 5. A film case according to claim 2, characterized by the fact that said clamping means further comprise a peripherically extending resilient means acting to move the segments of the clamping means toward the tube axis.
 6. A film case according to claim 1, characterized by the fact that it comprises means restricting the movement of the clamping means axially in a direction away from said stationary abutment surface. 